Institute of Translational Medicine , Zhejiang University , Hangzhou 310029 , China.
Department of Medical Oncology, Holistic Integrative Oncology Institute and Holistic Integrative Pharmacy Institute, The Affiliated Hospital of Hangzhou Normal University, College of Medicine , Hangzhou Normal University , Hangzhou 311100 , China.
ACS Appl Mater Interfaces. 2019 Aug 21;11(33):29569-29578. doi: 10.1021/acsami.9b09655. Epub 2019 Aug 12.
Circulating tumor cells (CTCs) in blood is the direct cause of tumor metastasis. The isolation and detection of CTCs in the whole blood is very important and of clinical value in early diagnosis, postoperative review, and personalized treatment. It is difficult to separate all types of CTCs that efficiently rely on a single path due to cancer cell heterogenicity. Here, we designed a new kind of "filter chip" for the retention of CTCs with very high efficiency by integrating the effects of cell size and specific antigens on the surface of tumor cells. The filter chip consists of a semicircle arc and arrays and can separate large-scale CTC microspheres, which combined with CTCs automatically. We synthesized interfacial zinc oxide coating with nanostructure on the surface of the microsphere to increase the specific surface area to enhance the capturing efficiency of CTCs. Microspheres, trapped in the arrays, would entrap CTCs, too. The combination of the three kinds of strategies resulted in more than 90% capture efficiency of different tumor cell lines. Furthermore, it is easy to find and isolate the circulating tumor cells from the chip as tumor cells would be fixed inside the structure of a filter chip. To avoid the high background contamination when a few CTCs are surrounded by millions of nontarget cells, a digital detection method was applied to improve the detection sensitivity. The CTCs in the whole blood were specifically labeled by the antibody-DNA conjugates and detected via the DNA of the conjugates with a signal amplification. The strategy of the antibody-functional microsphere-integrated microchip for cell sorting and detection of CTCs may find broad implications that favor the fundamental cancer biology research, the precise diagnosis, and monitoring of cancer in the clinics.
循环肿瘤细胞（CTCs）在血液中是肿瘤转移的直接原因。在全血中分离和检测 CTCs 对于早期诊断、术后复查和个性化治疗具有非常重要的临床价值。由于癌细胞的异质性，很难仅依靠一种途径来有效分离所有类型的 CTCs。在这里，我们设计了一种新型的“滤芯片”，通过整合细胞大小和肿瘤细胞表面特异性抗原的作用，非常有效地保留 CTCs。滤芯片由半圆形和阵列组成，可以分离出大规模的 CTC 微球，并与 CTC 自动结合。我们在微球表面合成了具有纳米结构的界面氧化锌涂层，以增加比表面积，提高 CTC 的捕获效率。被困在阵列中的微球也会捕获 CTCs。这三种策略的结合导致不同肿瘤细胞系的捕获效率超过 90%。此外，由于肿瘤细胞会被固定在滤芯片的结构内，因此从芯片上很容易找到并分离出循环肿瘤细胞。为了避免当少数 CTC 被数百万个非靶细胞包围时背景污染过高，应用了数字检测方法来提高检测灵敏度。用抗体-DNA 缀合物特异性标记全血中的 CTCs，并通过缀合物的 DNA 进行信号放大来检测。这种抗体功能微球集成微芯片用于 CTC 分选和检测的策略可能具有广泛的意义，有利于癌症生物学基础研究、临床精确诊断和癌症监测。
